The present invention relates to an image processing system and, more particularly, to an image processing system for use in displaying, storing and transmitting digital image data.
In conventional image processing systems, digital image data stored in a frame memory is written into a display memory. Character data or graph digital data is stored in an overlay memory. The data in the display and overlay memories is input to a monitor via a D/A converter, and an image and associated characters or graphs are displayed on the monitor. The image, character, and graph data are input in a video imager via a video output terminal, and are recorded on a film of the video imager.
With conventional image processing systems as described above, when the image, character, and graph data are recorded on the film by the video imager, the data supplied via the D/A converter are used. In this case, video signals must be input to the video imager in correspondence with the scanning line of the monitor. For this purpose, when a plurality of monitors having different scanning speeds are used, a plurality of imagers corresponding to the different scanning speeds must be connected to the respective monitors.
When image data is stored in a digital memory unit such as an optical disk, the image data must be input to the digital memory unit via a CPU bus line. Therefore, the CPU must execute a complicated program. More specifically, the contents and file numbers of the images currently displayed are sequentially checked, additional data (overlay data such as character data or graph data) relative to a file number selected thereby is read from a magnetic disk, and the image data corresponding to the selected file number is read from the magnetic disk. The data read from the magnetic disk is processed to correspond to the file number.